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1.
Environ Pollut ; 266(Pt 3): 115175, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32683088

RESUMEN

Detailed information on in-harbour shipping contribution to size segregated particles in coastal cities are scarce, especially in the busy Mediterranean basin. This poses issues for human exposure and air quality in urban harbour agglomerates, where only criteria pollutants (i.e. PM10 and/or PM2.5) are usually monitored. In this work, particle number and mass size distributions, in a large size range (0.01-31 µm), were obtained in two coastal cities of northern Adriatic Sea: Venice (Italy) and Rijeka (Croatia). Three size ranges were investigated: nanoparticles (diameter D < 0.25 µm); fine particles (0.25 1 µm). Absolute concentrations were larger in Venice for all size ranges showing, using analysis of daily trends, a large influence of local meteorology and boundary-layer dynamics. Contribution of road transport was larger (in relative terms) in Rijeka compared to Venice. The highest contributions of shipping were in Venice, mainly because of the larger ship traffic. Maximum impact was on nanoparticles 7.4% (Venice) and 1.8% (Rijeka), the minimum was on fine range 1.9% (Venice) and <0.2% (Rijeka) and intermediate values were found in the coarse fraction 1.8% (Venice) and 0.5% (Rijeka). Contribution of shipping to mass concentration was not distinguishable from uncertainty in Rijeka (<0.2% for PM1, PM2.5, and PM10) and was about 2% in Venice. Relative contributions as function of particles size show remarkable similitudes: a maximum for nanoparticles, a quick decrease and a successive secondary maximum (2-3 times lower than the first) in the fine range. For larger diameters, the relative contributions reach a minimum at 1-1.5 µm and there is a successive increase in the coarse range. Size distributions showed a not negligible contribution of harbour emissions to nanoparticle and fine particle number concentrations, compared to PM2.5 or PM10, indicating them as a better metric to monitor shipping impacts compared to mass concentrations (PM2.5 or PM10).


Asunto(s)
Contaminantes Atmosféricos/análisis , Navíos , Ciudades , Croacia , Monitoreo del Ambiente , Humanos , Italia , Tamaño de la Partícula , Material Particulado/análisis
2.
Cancer Res ; 55(11): 2236-9, 1995 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-7757970

RESUMEN

The human MAGE-3 gene encodes a melanoma antigenic epitope recognized by specific cytotoxic T lymphocytes, but its gene product has not been identified thus far. We produced a recombinant MAGE-3 gene product by expression cloning of the entire reading frame in the context of a fusion protein characterized by a 10-histidine tail, allowing purification by metal chelation on a nickel Sepharose column. The semipurified product was used to generate MAGE-3-specific monoclonal antibodies. One reagent could identify by immunoblotting the native MAGE-3 gene product as a M(r) 48,000 protein in lysates of cell lines showing evidence of MAGE-3 gene expression. No apparent cross-reactivity with recombinant or native MAGE-1 gene product was observed. Immunohistochemistry shows that, closely resembling the MAGE-1 gene product, MAGE-3 is a cytoplasmic protein.


Asunto(s)
Antígenos de Neoplasias/análisis , Proteínas de Neoplasias , Animales , Anticuerpos Monoclonales , Especificidad de Anticuerpos , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Secuencia de Bases , Clonación Molecular , Expresión Génica , Líquido Intracelular/química , Líquido Intracelular/inmunología , Melanoma/química , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Células Tumorales Cultivadas
3.
Eur J Cancer ; 29A(15): 2118-25, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8297651

RESUMEN

To obtain an insight into the network of cytokine gene transcription in the brain tumour microenvironment, we investigated the expression of genes encoding for interleukin (IL)-1 alpha, IL-1 beta, IL-2, IL-4, IL-5, IL-6, IL-10, interferon (IFN)-gamma, granulocyte-macrophage colony-stimulating factor, tumour necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta 1, -beta 2 and -beta 3 in freshly excised brain tumour samples and autologous peripheral blood mononuclear cells. Tissue specimens from 15 primary brain tumours, three brain metastases, five meningiomas, autologous peripheral blood mononuclear cells (PBMC) and three brain tumour cell lines were tested by reverse polymerase chain reaction. Despite the presence of T-lymphocytes, cytokine gene transcripts typically detectable upon T cell receptor triggering could not be observed in central nervous system tumours of diverse histology. In primary brain neoplasms, transcription of genes encoding for the inhibitory cytokines TGF-beta and IL-10 was detectable in more than 50% of samples. IL-6 transcripts could only be detected in malignant gliomas. In brain metastases, virtually no cytokine gene transcripts could be observed. Surprisingly, TGF-beta transcripts were also detected in all meningiomas. Thus, transcription of genes encoding for inhibitory factors appears to prevail in primary brain neoplasms.


Asunto(s)
Neoplasias Encefálicas/genética , Citocinas/genética , Regulación Neoplásica de la Expresión Génica/inmunología , Meningioma/genética , Transcripción Genética/inmunología , Adolescente , Adulto , Anciano , Secuencia de Bases , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/secundario , Preescolar , ADN de Neoplasias/química , Femenino , Humanos , Masculino , Meningioma/inmunología , Persona de Mediana Edad , Datos de Secuencia Molecular , Células Tumorales Cultivadas
4.
Hum Immunol ; 43(1): 45-50, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7558928

RESUMEN

MHC class II determinants are the restriction elements involved in antigen-specific activation of helper T lymphocytes and interaction with CD4 molecules. They are typically expressed on a limited number of cell types, mostly endowed with antigen-presenting capacity. Recently, expression of HLA-DR has been detected on granulocytes stimulated "in vitro" with GM-CSF. However, no evidence of "in vivo" expression in humans has been presented so far. We report here that class II determinant expression is detectable in vivo on peripheral blood granulocytes of polytraumatized patients upon intravenous administration of rhGM-CSF. Expression of these molecules appears to be an early effect of rhGM-CSF treatment, independent from endotoxemia or endogenous production of IL-6 or TNF-alpha, and rapidly declining upon discontinuation of therapy. Thus, this treatment might increase the number of cells potentially capable of presenting class-II-restricted antigens in these patients.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Granulocitos/efectos de los fármacos , Antígenos HLA-DR/efectos de los fármacos , Traumatismo Múltiple/inmunología , Adulto , Anciano , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Granulocitos/metabolismo , Antígenos HLA-DR/metabolismo , Humanos , Interleucina-6/sangre , Persona de Mediana Edad , Traumatismo Múltiple/terapia , Proteínas Recombinantes/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo
5.
Immunobiology ; 202(5): 421-8, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11205372

RESUMEN

Immune system maturation proceeds postnatally in humans. Therefore, newborns, especially those of a lower gestational age, are not fully immunocompetent and are more likely to acquire perinatal infections. In order to investigate the neonatal immune system status, the major lymphocyte subpopulations were studied in newborns of different gestational age, comparing term newborns and adults. The cord blood from 66 newborns and the peripheral blood from 23 adults were analyzed using fluorochrome labelled monoclonal antibodies and two-color flow cytometry. The newborns were divided into three groups according to their gestational age. Ten prematures were under 32 weeks of gestation, 35 were of 32-37 weeks and there were 21 term newborns. The percentage of cytotoxic T lymphocytes (CD4 CD8+) was lower in term newborns as compared to the adult controls (17.8 versus 30.3%), and so were the percentages of activated T lymphocytes (CD3+Ia+; 0.3 versus 3.7%), cytotoxic non-MHC restricted T lymphocytes (CD3+CD16+CD56+; 0.2 versus 1.8%) and NK cells (CD3-CD16+CD56+; 4.8 versus 15.5%). On the contrary, the proportions of unlabelled cells were increased in term cord blood. The expression of CD45R0 marker on neonatal lymphocytes was very low (1%). In comparison to the higher-gestation newborns, the lower gestation prematures had reduced percentages of T lymphocytes (CD3+; 43 versus 65%), mostly helper T lymphocytes (CD4+CD8-; 35 versus 50%), and increased percentages of unlabelled cells. The percentages of NK cells (CD3+CD16+CD56+) and B lymphocytes (CD3-CD19+; CD3-Ia+) did not differ among the tested newborn groups. There were no significant differences in major lymphocyte subpopulations between the group of highest-gestation prematures and the group of term newborns that differed significantly when compared to adults. The lowest-gestation newborns showed the most immature lymphocyte phenotype with the highest percentages of unlabelled cells.


Asunto(s)
Citometría de Flujo/métodos , Recien Nacido Prematuro/inmunología , Subgrupos Linfocitarios/inmunología , Antígenos CD19/análisis , Linfocitos B/inmunología , Complejo CD3/análisis , Antígenos CD4/análisis , Antígeno CD56/análisis , Antígenos CD8/análisis , Femenino , Antígenos de Histocompatibilidad Clase II/análisis , Humanos , Recién Nacido , Células Asesinas Naturales/inmunología , Antígenos Comunes de Leucocito/análisis , Masculino , Receptores de IgG/análisis , Linfocitos T Citotóxicos/inmunología
6.
APMIS ; 99(3): 213-8, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1850285

RESUMEN

Cytotoxic T-lymphocyte precursors (CTL-P) from control C57BL/6 mice and from mice of two simian virus 40 (SV40) T-antigen transgenic lines, 427 and 419, specifically nonresponsive and responsive, respectively, to SV40 T antigen, were quantitated by limiting dilution (LD) after immunization with SV40. CTL-P frequencies for the SV40 T antigen-responsive 419 line transgenic mice were within the range established in C57BL/6 mice, whereas no CTL-P could be demonstrated for the SV40 T antigen-tolerant 427 line mice. These results suggest that deletion or anergy of SV40 T antigen-responsive clones underlies the specific profound tolerance of 427 line mice.


Asunto(s)
Antígenos Transformadores de Poliomavirus/inmunología , Virus 40 de los Simios/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Línea Celular , Células Cultivadas , Citotoxicidad Inmunológica , Ganglios Linfáticos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Probabilidad , Valores de Referencia , Virus 40 de los Simios/genética
7.
Virchows Arch ; 439(2): 127-31, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11561752

RESUMEN

MAGE (Melanoma antigen E) family gene products encompass tumour-associated antigens (TAAs) recognised by human leukocyte antigen (HLA)-restricted specific T-cells. Agents inducing DNA demethylation, an event typically detectable in cellular de-differentiation processes, were shown to induce the expression of MAGE genes. By using a monoclonal antibody specific for MAGE family gene products, we have studied the expression of these TAAs in a group of 144 patients with invasive ductal breast cancers. Immunohistochemical data were correlated with tumour differentiation, lymphatic vessel invasion, oestrogen receptor expression, intratumoural necrosis, lymphocytic infiltration, perineural invasion, tumour microcalcifications and axillary lymph node metastases. MAGE immunoreactivity was undetectable in non-neoplastic cells. In poorly differentiated cancers positive staining was observed in 30/63 cases (47.6%) as compared with 13/51 (25.4%) and 5/30 (16.6%) in moderately and well-differentiated tumours, respectively (P<0.05). In addition, MAGE immunoreactivity was significantly correlated with lymphatic vessel invasion and intratumoural necrosis. Moreover, a significant inverse relationship with oestrogen receptor expression was also observed. However, no significant correlation could be established between MAGE immunoreactivity and defined phenotypic characteristics of tumour infiltrating lymphocytes, including expression of CD3, CD4, CD8, CD20 or granzyme B. Thus, expression of MAGE family gene products in invasive ductal breast cancers appears to be associated with poorly differentiated histological phenotypes. These data support the concept of specific immunotherapy in highly aggressive forms of breast neoplasms. Furthermore, they suggest that MAGE immunoreactivity could represent a tumour marker of potential prognostic relevance.


Asunto(s)
Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Proteínas de Neoplasias/metabolismo , Anticuerpos Monoclonales , Antígenos de Neoplasias , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/clasificación , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/clasificación , Carcinoma Ductal de Mama/secundario , Recuento de Células , Diferenciación Celular , Transformación Celular Neoplásica , Femenino , Humanos , Técnicas para Inmunoenzimas , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Metástasis Linfática , Antígenos Específicos del Melanoma , Invasividad Neoplásica/patología , Proteínas de Neoplasias/inmunología
8.
Breast ; 13(6): 530-2, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15563865

RESUMEN

We report the case of a 59-year-old woman who presented with right flank pain and fever. Diagnostic investigations revealed stenosis of the right ureter extending over about 1cm. Since a double-J prosthesis could not be passed through it, a percutaneous nephrostomy was constructed and surgical exploration and excision of the stenotic ureteral segment were then carried out. Histopathological analysis of the segment removed showed diffuse infiltration with epithelial tumor cells. On immunohistochemistry, these cells were found to be positive for cytokeratin and for estrogen and progesterone receptors. No primary cancer and no additional metastases were detected. Eleven months later a primary tumor with a metastasis in the left supraclavicular region was found in the patient's right breast.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma Lobular/secundario , Neoplasias Primarias Desconocidas , Neoplasias Ureterales/secundario , Neoplasias de la Mama/diagnóstico , Carcinoma Lobular/diagnóstico , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Factores de Tiempo , Neoplasias Ureterales/patología
9.
J Neurosurg ; 78(4): 630-7, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8450337

RESUMEN

The use of tumor-infiltrating lymphocytes in the treatment of central nervous system (CNS) neoplasms has met with serious obstacles due to difficulty of culture and poor characterization. Since in other tumors the therapeutic effects of tumor-infiltrating lymphocytes have been shown to rely on T-cell receptor engagement, the authors addressed the question as to whether expression of T-cell receptor variable (V) domains in cultured tumor-infiltrating lymphocytes from CNS is different from that of autologous cultured peripheral blood mononuclear cells. Infiltrating lymphocytes from CNS neoplasms, including primary malignancies, metastatic cancers, and meningiomas, were cultured in the presence of interleukin-2 and anti-CD3 monoclonal antibodies (MoAb's) in order to obtain optimum growth of T cells. Autologous peripheral blood mononuclear cells from the same patients were similarly cultured. After 4 to 5 weeks of culture, 97.3% +/- 2.6% (mean +/- standard deviation) of the resulting cell populations were CD3-positive lymphocytes. The expression of T-cell receptor V domains was then studied by using a panel of 12 MoAb recognizing gene products from T-cell receptor V-alpha 2, V-beta 5, 6, 8, and 12, V-gamma 4 and 9 families, and from two subfamilies of V-delta 2. Remarkably, in over 70% of all paired measurements, percentages of T cells expressing discrete T-cell receptor V-gene products were found to be virtually identical in tumor- and peripheral blood-derived cultured cell populations, with differences never exceeding 1%. In contrast, a different expression of individual V-gene products, concerning both alpha/beta and gamma/delta T-cell receptors, could be detected between cultured tumor-infiltrating lymphocytes and autologous peripheral blood-derived T lymphocytes in seven of 12 patients. In two cases, significant differences between the two populations were also observed in the proliferative responses obtained upon stimulation with staphylococcal enterotoxins that trigger defined V-beta T-cell receptors. Altogether, these data suggest that the T-cell receptor repertoire of cultured tumor-infiltrating lymphocytes from CNS tumors, suitable for use in adoptive immunotherapies, differs from that of autologous cultured peripheral blood mononuclear cells.


Asunto(s)
Neoplasias del Sistema Nervioso Central/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Receptores de Antígenos de Linfocitos T/genética , Linfocitos T/inmunología , Adulto , Anciano , División Celular , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/patología , Neoplasias del Sistema Nervioso Central/terapia , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunofenotipificación , Linfocitos Infiltrantes de Tumor/patología , Masculino , Persona de Mediana Edad , Linfocitos T/patología , Células Tumorales Cultivadas
10.
Clin Nutr ; 13(1): 42-9, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16843351

RESUMEN

The role of glutamine (GLN) in the generation of lymphokine-activated killer (LAK) cell activity was investigated. LAK cells were derived from healthy donors and peripheral blood mononuclear cells (PBMC) were obtained using either unseparated PMBC or DR(-) CD3(-) CD16(+) CD56(+) enriched cells. PBMC were cultured for 6 or 10 days in medium supplemented with recombinant interleukin-2 (rlL-2; 100 U/ml) in the presence of different concentrations of GLN. K562 (natural killer-NK-sensitive targets), 1301 and U-937 (NK-resistant targets) cells were used as targets in the cytotoxic assays. Furthermore, the limiting dilution (LD) culture system was applied as an alternative to the bulk cell culture system. It was found that GLN affects the lytic potential of cultured cells while the frequency of responding cells did not significantly differ between the compared cell cultures performed in the presence of different amounts of GLN. Data on cell proliferation with IL-2 stimulation showed significant differences in cultures performed in the presence or absence of GLN. The results of present investigation suggest a supportive role of GLN in the generation of LAK cells. GLN deficit affects LAK cell killing activity by limiting the number of generated effector cells while acquisition of broad-range killing capacity was not affected.

11.
Clin Nutr ; 15(1): 16-20, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16843989

RESUMEN

Nitric oxide (NO) derived intracellularly from L-arginine (Arg) is indispensable for optimalgeneration of lymphokine-activated killer (LAK) cell activity in rodents. Still unclear, however, is its role in humans. To address this question human peripheral blood mononuclear cells (PBMC) from healthy donors were cultured in L-arginine free medium supplemented with recombinant interleukin-2 (rIL-2) and in the presence of exogenous L-arginine analog NG-monomethyl-L-arginine (NMMA), a specific inhibitor of the NO synthetic pathway. Cultured PBMC were tested for cytotoxic activity, proliferative capacity, and expression of phenotypic and activation markers (CD3, CD4, CD8, CD16, CD56 and CD25). Culture supernatants were assayed for nitrite (NO2-) and tumor necrosis factor-alpha (TNF-alpha) production. We found that NMMA inhibits the generation of optimal LAK cell activity when no exogenous Arg is supplied. Similar effects were also observed on proliferation, expression of IL-2 receptor induced upon rIL-2 stimulation and on TNF-alpha production. Sodium nitroprusside (SNP), used as a source of exogenous NO could not overcome this effect of NMMA on LAK cell activity. NO2- production was virtually undetectable in culture supernatants. Thus, NMMA affects in an NO-independent manner rlL-2 induced LAK activity in human PBMC.

12.
Nutrition ; 12(11-12 Suppl): S71-2, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8974122

RESUMEN

The dependence of human lymphocyte functions on the exogenous provision of glutamine (GLN) was evaluated in a series of in vitro experiments. The transcription of early activation markers (IL-2, IL-2-receptor, IL-4, IL-4, GM-CSF, IFN gamma) as evaluated by polymerase chain reaction was observed even in the absence of exogenous GLN. In contrast, later events of lymphocyte activation including cytokine production, proliferation of lymphocytes and lymphokine-activated killer cell activity were found to depend on exogenous GLN provision. These in vitro results are discussed in the context of established data on the reduction of peripheral blood GLN concentrations in critically ill patients and in view of recent studies reporting improved outcome of critically ill patients following GLN substitution. By and large, these data support the concept of GLN substitution in critical illness. However, the definition of indications and dose-response relationships clearly require further clinical studies.


Asunto(s)
Enfermedad Crítica , Glutamina/fisiología , Inmunidad , Células Cultivadas , Citocinas/biosíntesis , Citocinas/genética , Glutamina/farmacología , Humanos , Células Asesinas Activadas por Linfocinas/efectos de los fármacos , Células Asesinas Activadas por Linfocinas/inmunología , ARN Mensajero/análisis , Linfocitos T/inmunología
13.
JPEN J Parenter Enteral Nutr ; 24(6): 337-44, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11071593

RESUMEN

BACKGROUND: The lipid component of total parenteral nutrition (TPN) has reportedly been associated with trophic effects on the intestinal mucosa and suppressive effects on the immune system. METHODS: We have challenged these hypotheses using a 7-day TPN rodent model comparing the effects of isocaloric, isonitrogenous lipid-based (TPN-lipid, 50% of calories as long-chain triacylglycerol) and carbohydrate-based TPN (TPN-CH, 100% of calories as carbohydrates) on mucosal morphology and immune function. Enterally fed animals were included to establish a baseline for immunologic read-outs. The study was performed in healthy, metabolically stable animals to avoid interference by septic or trauma-related stress factors. RESULTS: Both TPN regimens resulted in a significantly smaller weight gain (TPN-lipid, 29.8 +/- 4.0 g; TPN-CH, 30.3 +/- 4.4 g) compared with enterally fed reference animals (49.2 +/- 3.2 g; p = .007), with no difference in nitrogen balance between the TPN groups. Mucosal sucrase activity was significantly lower in both TPN groups (TPN-lipid, 8.8 +/- 1.0 x 10(-7) katal per gram (kat/g) of protein; CH: 11.9 +/- 1.6 x 10(-7) kat/g of protein) compared with enteral feeding (17.4 +/- 0.9 x 10(-7) kat/g of protein; ANOVA: p = .0007). Morphometric analysis of the small intestine revealed no differences between the two TPN groups although a significantly depressed villus height in the TPN-lipid group could be observed in comparison to enterally fed reference rats (TPN-lipid, 0.47 +/- 0.02; TPN-CH, 0.50 +/- 0.01; enteral, 0.56 +/- 0.02 mm; ANOVA: p = .0298). Light and electron microscopy revealed a normal surface architecture in all three groups of rats. Cellular immune reactivity was evaluated using a novel specific immunization protocol: animals were immunized against OVA 4 weeks before TPN. OVA-induced lymphoproliferative responses and phenotypic data from draining popliteal and mesenteric lymph nodes were evaluated after the different regimens. Results did not differ among the three groups. CONCLUSIONS: In healthy rodents, short-term lipid-based and carbohydrate-based TPN regimens lead to limited mucosal atrophy with preserved surface architecture compared with enteral feeding. However, peripheral and mesenteric cellular immune responsiveness after both TPN regimens remained comparable to enterally fed reference animals. Therefore, mesenteric and systemic cellular immune reactivity does not appear to be impaired by lipid-based or carbohydrate-based TPN.


Asunto(s)
Emulsiones Grasas Intravenosas/administración & dosificación , Mucosa Intestinal/inmunología , Nutrición Parenteral Total , Animales , Atrofia , Carbohidratos/administración & dosificación , Citometría de Flujo , Inmunidad Celular , Inmunización , Mucosa Intestinal/patología , Mucosa Intestinal/ultraestructura , Ganglios Linfáticos/citología , Ganglios Linfáticos/inmunología , Masculino , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Nitrógeno/metabolismo , Distribución Aleatoria , Ratas , Ratas Wistar , Linfocitos T/inmunología , Aumento de Peso
14.
Sci Total Environ ; 192(2): 207-12, 1996 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-8956527

RESUMEN

Zinc levels were determined in human milk and umbilical cord blood samples collected in the Rijeka Clinical Hospital during the period from September 1995 to January 1996. The average concentrations of zinc were 4.98 +/- 2.53 mg/l in breast milk (range: 1.69-11.60 mg/l) and 1.18 +/- 0.21 mg/l in umbilical cord blood (range: 0.87-1.91 mg/l). Results of group comparisons regarding mothers' age, parity, residence and smoking habits indicate that parity affected Zn levels in both, breast milk and umbilical cord blood, with higher content found in primiparae. Younger mothers (aged < or = 25 years) also had higher levels of Zn in breast milk compared to those whose age was > 25 years. Residence and smoking habits did not seem to have any impact on Zn concentrations in biological tissues studied. A weak association between umbilical cord blood Zn levels and anthropometric measurements of newborns, like birthweight and head circumference, is also observed.


Asunto(s)
Sangre Fetal/química , Leche Humana/química , Cordón Umbilical , Zinc/análisis , Adolescente , Adulto , Análisis de Varianza , Peso al Nacer , Femenino , Humanos , Recién Nacido , Persona de Mediana Edad , Embarazo , Estadísticas no Paramétricas
15.
Chemosphere ; 41(5): 667-70, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10834366

RESUMEN

Earlier results on ozone destruction on solid surfaces gave apparent first order kinetics. Estimating the reaction kinetics from our data on ozone destruction on various powders (silica-gel, alumina, wood ash, coal ash, Saharan sand, calcite), we found that only calcite and wood ash exhibited such a behaviour. Removal of ozone by other powders used showed two straight lines in ln c-t plot with two different half-lives, t'(1/2) < t''(1/2). Comparing the kinetic constants for ozone removal on silica-gel and that of ozone reactions with polynuclear aromatic hydrocarbons (PAHs) adsorbed in submonolayer coverage on the same powder, the first reaction seems to be more likely in the case of pyrene and particularly fluoranthene. Enhanced ozone destruction on airborne aerosols could be an additional reason for fluoranthene stability in the real atmosphere.


Asunto(s)
Ozono/química , Hidrocarburos Policíclicos Aromáticos/química , Reactores Biológicos , Geles , Cinética , Polvos/química , Propiedades de Superficie
16.
ScientificWorldJournal ; 1 Suppl 2: 343-7, 2001 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-12805874

RESUMEN

The determination of ambient levels of nitrogen dioxide (NO2) and ammonia (NH3) in the Rijeka Bay area started in 1980, as a part of the air quality monitoring programme. The results of 15 years of surveying (1980/81-1994/95) on ambient levels of these pollutants at two sampling sites are given in this work. Site 1 is located in the city, opposite the old petroleum refinery facilities, while Site 2 is located in the settlement 25 km from the city, opposite the eastern industrial zone. Annual means of NO2 varied between 34 and 60 g/m3 at Site 1 and between 14 and 26 g/m3 at Site 2, but do not follow the 40% reduction in industrial emissions of this pollutant, probably due to the dominant impact of other minor sources, like traffic. Yearly averages of NH3 were in the range of 13 to 26 g/m 3 at Site 1 and 7 to 16 g/m3 at Site 2, and are practically constant during the period studied.


Asunto(s)
Contaminantes Atmosféricos/análisis , Amoníaco/análisis , Monitoreo del Ambiente/estadística & datos numéricos , Dióxido de Nitrógeno/análisis , Croacia , Monitoreo del Ambiente/métodos , Geografía , Industrias , Estaciones del Año , Dióxido de Azufre/análisis
17.
Arh Hig Rada Toksikol ; 51(2): 249-56, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11103529

RESUMEN

Protection against corrosion in the shipyard is a source of airborne particles. From October 1996 to September 1997 samples of suspended particles (1 site) and dustfall (6 sites) were collected in the vicinity of a repairs shipyard situated in the martinscica Cove, east of the city of Rijeka, Croatia. Collected samples were analysed for lead, cadmium, iron, copper, and zinc content. Though annual mean concentrations of suspended particles, lead, and cadmium kept below the guideline values, the metal contents were generally higher than values measured in the city centre. The correlation between the quantity of abrasives used at the shipyard and monthly mean concentrations of all parameters except cadmium suggests that the shipyard was the main source of those pollutants. The annual mean, as well as maximum monthly amount of dustfall at the site next to the shipyard zone exceeded the national limit values, indicating considerable pollution of this area with coarse particles. The annual mean quantity of lead in dustfall exceeded the guideline values at the same site. The content of metals occasionally observed in dustfall at particular sites surrounding the shipyard depended on the location of corrosion protection activities and meterological conditions within the Martinscica Cove.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Metales/análisis , Croacia , Industrias , Navíos
18.
Arh Hig Rada Toksikol ; 49(2): 155-63, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9919721

RESUMEN

During the eighties the city of Rijeka was one of the most polluted cities in Croatia with sulphur dioxide due to high emission of this pollutant from industrial plants. In mid-eighties, annual means of SO2 exceeded 100 micrograms/m3 in the city centre, in the Bakar Bay area varied between 70-80 micrograms/m3, while in the suburban residential area they were up to 40 micrograms/m3. In 1995 annual means were below the guideline value of 50 micrograms/m3 in the whole Rijeka Bay area. Emission inventory based on 1989 data estimated total SO2 emission to approximately 36,000 t a year, 95% of which from industrial sources. The update from 1995 data gave a new estimate of approximately 11,000 t a year, which is a 70.5% reduction of SO2 emission. However, the contribution of emissions from industrial sources remained practically unchanged (95%). The emission reduction resulted in the decrease of ambient levels of SO2. The paper presents trends in SO2 annual mean concentrations in the period 1986-1995 for two urban sites, two sites situated in the industrial area east of the city, and a suburban residential site.


Asunto(s)
Contaminantes Atmosféricos/análisis , Dióxido de Azufre/análisis , Croacia
19.
Arh Hig Rada Toksikol ; 49(3): 245-50, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10376356

RESUMEN

This study compares the chemical composition of rainwater samples collected at two sampling sites, the first situated in the Rijeka city centre and the second in a suburban site 120 m above the sea level. The rainwater samples were analysed for precipitation weighted average concentrations of hydrogen, sulphate, nitrate, chloride, ammonium, sodium, potassium, calcium, and magnesium. The results suggest that the local washout of the atmosphere enhanced the rainwater acidity in the city centre which also received significant marine contributions of sulphate, calcium, magnesium, and potassium content. Rainwater in the suburban site was affected by soil dust and/or fertilizers used in the nearby gardens, resulting in partial neutralization with rising of pH value. While the content of S-SO4 was practically equal at both sites, the quantities of N-NO3 and N-NH4 nearly doubled at the suburban site.


Asunto(s)
Lluvia , Contaminantes Químicos del Agua/análisis , Croacia , Humanos
20.
Arh Hig Rada Toksikol ; 40(3): 319-33, 1989 Sep.
Artículo en Croata | MEDLINE | ID: mdl-2700548

RESUMEN

Toxicological properties of polynuclear aromatic hydrocarbons (PAH) and their derivatives concerning their carcinogenicity, embryotoxicity and phototoxicity are reviewed. The importance of the Ames test and biologically directed chemical analysis for identification of these mutagenic compounds is emphasized. Possible chemical reactions acting as sources of mutagenic PAH derivatives in the atmosphere are given.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Compuestos Policíclicos/toxicidad , Animales , Fenómenos Químicos , Química , Pruebas de Mutagenicidad , Compuestos Policíclicos/farmacocinética
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